Eco-friendly gas insulating medium for next-generation SF₆-free equipment

Abstract

Gas-insulated equipment (GIE) that utilizes the most potent greenhouse gas sulfur hexafluoride (SF 6 ) as insulation and arcquenching medium has been widely used in the power industry. Seeking eco-friendly insulating gas with advanced performance for next-generation SF 6 -free GIE is significant for the "net-zero" goal and sustainable development. In this paper, the utilization, emission, and reduction policies of SF 6 around the world were summarized first. Then, we systematically reviewed the latest progress in comprehensive performance evaluation of eco-friendly insulating gas in terms of molecular design, dielectric insulation, arcquenching, stability and decomposition, materials compatibility, biosafety, etc. Further, the representative applications of ecofriendly insulating gas in medium-voltage, high-voltage GIE as well as relevant maintenance-related technologies were highlighted. Accordingly, the existing challenges and future perspectives were proposed, presenting a roadmap to hopefully steer the development of eco-friendly insulating gas and GIE. KEYWORDSEco-friendly insulating gas, net-zero, dielectric insulation, arc-quenching, SF 6 -free gas-insulated equipment (GIE).

Stability Valorization of Hydrofluoroolefine HFO-1336mzzE and Its Mixtures under Arc Discharge Conditions

“…In these studies, different qualities of the gases have been analyzed and compared, such as dielectric properties, arc-quenching, stability decomposition, material compatibility, and biosafety. 12 Ormazabal Corporate Technology (Spain, Bizkaia) suggested hydrofluorolefine 1,1,1,1,4,4,4hexafluorobut-2-ene or HFO-1336mzz (E), hereafter referred to as HFO4E, as a viable alternative to SF 6 due to its good dielectric strength and low GWP. Moreover, five EU countries have recently submitted a proposal to the European Chemicals Agency (ECHA) to restrict the use of compounds containing −CF 3 or −CF 2 − in their chemical structure (fluorinated compounds in general).…”

“…More eco-friendly alternatives to SF 6 in gas insulated equipment (GIE) have been explored in recent years, such as ketones, fluorinated nitrile, and hydrofluoro-olefins. In these studies, different qualities of the gases have been analyzed and compared, such as dielectric properties, arc-quenching, stability decomposition, material compatibility, and biosafety . Ormazabal Corporate Technology (Spain, Bizkaia) suggested hydrofluorolefine 1,1,1,1,4,4,4-hexafluorobut-2-ene or HFO-1336mzz (E), hereafter referred to as HFO4E, as a viable alternative to SF 6 due to its good dielectric strength and low GWP.…”

Assessment on gas‐polyethylene terephthalate solid interface partial discharge properties of C4F7N/CO2 gas mixture for eco‐friendly gas insulating transformer

“…In recent years, perfluoroisobutyronitrile (C 4 F 7 N) has been considered as one of the most promising alternative gases. Its GWP is 2090 and its dielectric strength is more than twice than that of SF 6 [12][13][14]. Due to the high liquefaction temperature (−4.7°C), C 4 F 7 N needs to be mixed with buffer gases such as CO 2 to meet the minimum operating temperature requirements of the equipment [15,16].…”